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Designing a high‐performance cathode is essential for the development of proton‐conducting solid oxide fuel cells (H‐SOFCs), and nanocomposite cathodes have proven to be an effective means of achieving this. However, the mechanism behind the nanocomposite cathodes' remarkable performance remains unknown. Doping the Co element into BaZrO3 can result in the development of BaCoO3 and BaZr0.7Co0.3O3 nanocomposites when the doping concentration exceeds 30%, according to the present study. The construction of the BaCoO3/BaZr0.7Co0.3O3 interface is essential for the enhancement of the cathode catalytic activity, as demonstrated by thin‐film studies using pulsed laser deposition to simulate the interface of the BCO and BZCO individual particles and first‐principles calculations to predict the oxygen reduction reaction steps. Eventually, the H‐SOFC with a BaZr0.4Co0.6O3 cathode produces a record‐breaking power density of 2253 mW cm−2 at 700°C. [ABSTRACT FROM AUTHOR]

Novel magneto‐optical (MO) properties can be actualized through well‐designed nanostructures, greatly improving the application value of MO effects. As only p‐polarized light can generate transverse magneto‐optical Kerr effect (TMOKE) in traditional MO materials, it is quite challenging and valuable to effectuate TMOKE under s‐polarization incidence at optical frequencies. The constructed nanopillar structures in this work can realize a clear TMOKE under both s‐polarization and p‐polarization incidences, as proved by experiments and simulations. Under s‐polarized incident light with an elevation angle of 45°, electric dipole resonance (EDR) and electric quadrupole resonance (EQR) are excited, resulting in the significant enhancement of TMOKE (five orders of magnitude higher than for the planar Co film). The intensity of s‐polarized TMOKE shows an increase with the enhancing diameter and height of the nanopillar structure. The amplitude of p‐polarized TMOKE is also appreciably increased due to the excitation of surface plasmon polaritons (SPPs) and localized surface plasmons (LSPs). Moreover, the Fe and Ni nanopillars display similar reflectivity and s‐polarized TMOKE behaviors in simulations. The s‐polarized TMOKE is unexpectedly observed in ferromagnetic metals for the first time, which builds up a considerable platform for the development and application of novel MO phenomena. [ABSTRACT FROM AUTHOR]

As a benchmark triple‐conducting cathode, BaCo0.4Fe0.4Zr0.1Y0.1O3−δ (BCFZY) has been widely investigated for protonic ceramic fuel cells (PCFC) in recent years. However, the reported electrochemical performance of BCFZY cathode differs, which is determined in this work to originate from the thermal expansion mismatch between BCFZY and electrolyte. Accordingly, two strategies for enhanced thermo‐mechanical compatibility are examined: impregnation and thermal expansion offset. In contrast to the impregnation of BCFZY nanoparticles on electrolyte backbones that only helps improve electrochemical performance, negative thermal expansion oxide Sm0.85Cu0.15MnO3−δ (SCM)‐offset BCFZY exhibits superior durability and activity simultaneously. Specifically, the polarization resistance decay rate of the SCM‐offset BCFZY is only ~0.2%/100 h, compared with ~18.75%/100 h for "impregnated BCFZY." Moreover, pure SCM generates moderate cathodic performance (area‐specific resistance = 0.11 Ω cm2, 700 °C), X‐ray diffraction and transmission electron microscopy reveal an in‐situ formed intergranular Ba2Cu3SmO7−δ phase at the boundaries of BCFZY and SCM. Thus, SCM can serve as a "three‐effect" additive, i) offset thermo‐expansion, ii) strengthen electrode structure and adhesion, and iii) provide acceptable oxygen‐reduction‐reaction activity, being favorable for superior performance. A PCFC using a SCM‐offset BCFZY cathode achieves the highest power density (1455 mW cm−2) yet recorded for PCFCs with BCFZY‐based cathodes. [ABSTRACT FROM AUTHOR]

Polarization imaging enables the capture of material properties and surface characteristics of objects, finding applications in remote sensing and defense. However, most existing polarization imaging systems rely on polarization filtering elements, resulting in energy loss exceeding 50% and compromising intensity imaging performance. Conventionally, a rotary device equipped with different polarizers and a blank area is used to acquire both polarization and intensity images, which is cumbersome for integration and miniaturization purposes. In this study, a miniaturized and easily integrated active metasurface based on VO2 grating structure for switchable detection of intensity and polarization in the far‐infrared band (8–14 µm) is proposed. With VO2 in the dielectric state, the device exhibits high transmittance for both TE‐ and TM‐polarized light (Experimental transmittance of up to 65%). Upon phase transition to the metallic state, the device demonstrates low transmittance for TE‐polarized light while maintaining high transmittance for TM‐polarized light (linear polarization extinction ratio up to 10 dB). Finally, the tunable thermal intensity and polarization imaging capabilities of the custom‐made setup are characterized. The metasurface showcases comparable performance to standard commercial polarizers in terms of polarization imaging. The developed tunable far‐infrared polarization imaging system holds promise for next‐generation multidimensional information perception. [ABSTRACT FROM AUTHOR]

Background: Posterior capsular opacification (PCO) is a common complication following cataract surgery that leads to visual disturbances and decreased quality of vision. The aim of our study was to employ a machine‐learning methodology to characterize and validate enhancements applied to the grey‐level co‐occurrence matrix (GLCM) while assessing its validity in comparison to clinical evaluations for evaluating PCO. Methods: One hundred patients diagnosed with age‐related cataracts who were scheduled for phacoemulsification surgery were included in the study. Following mydriasis, anterior segment photographs were captured using a high‐resolution photographic system. The GLCM was utilized as the feature extractor, and a supported vector machine as the regressor. Three variations, namely, GLCM, GLCM+C (+axial information), and GLCM+V (+regional voting), were analyzed. The reference value for regression was determined by averaging clinical scores obtained through subjective analysis. The relationships between the predicted PCO outcome scores and the ground truth were assessed using Pearson correlation analysis and a Bland–Altman plot, while agreement between them was assessed through the Bland–Altman plot. Results: Relative to the ground truth, the GLCM, GLCM+C, and GLCM+V methods exhibited correlation coefficients of 0.706, 0.768, and 0.829, respectively. The relationship between the PCO score predicted by the GLCM+V method and the ground truth was statistically significant (p < 0.001). Furthermore, the GLCM+V method demonstrated competitive performance comparable to that of two experienced clinicians (r = 0.825, 0.843) and superior to that of two junior clinicians (r = 0.786, 0.756). Notably, a high level of agreement was observed between predictions and the ground truth, without significant evidence of proportional bias (p > 0.05). Conclusions: Overall, our findings suggest that a machine‐learning approach incorporating the GLCM, specifically the GLCM+V method, holds promise as an objective and reliable tool for assessing PCO progression. Further studies in larger patient cohorts are warranted to validate these findings and explore their potential clinical applications. [ABSTRACT FROM AUTHOR]

Efficient and accurate computation of the single‐scattering properties of black carbon (BC) aerosols is fundamental in various fields, including remote sensing and climate simulations. In this study, we developed a composite model of fractal aggregates of BC encapsulated with hygroscopic aerosols to represent the ambient BC. We used the invariant imbedding T‐matrix method to compute the optical properties of fully and partially encapsulated BC aerosols. In this new model, the traditional assumption of unoverlapped surfaces in the super‐position T‐matrix method is unnecessary. After extensive simulations, we established a database of single‐scattering properties, including the extinction efficiency, the single‐scattering albedo, the asymmetry factor and six phase matrix elements. Moreover, we obtained deep neural networks (DNNs) from this database using a deep learning method. These DNN models provide a universal interface for predicting the optical properties of ambient BC aerosols. Specifically, through a modified architecture of the DNN, we trained two models based on the database to predict three integrated optical properties (extinction efficiency, single‐scattering albedo, and asymmetry factor) and six phase matrix elements. We performed statistical assessments based on the true values in the database and the predicted values from the DNNs, demonstrating that the DNNs accurately predicted all single‐scattering properties. Therefore, the developed DNN models can be conveniently implemented in aerosol optical parameterization for remote sensing studies and atmospheric models. Plain Language Summary: Black carbon (BC) aerosol plays a significant role in the atmosphere, influencing climate through its interactions with radiation, such as scattering and absorbing. The accurate determination of the single‐scattering properties of BC, including the extinction efficiency, the single‐scattering albedo, the asymmetry factor and six phase matrix elements, is crucial for understanding its radiation effects. In this study, we developed a comprehensive model for BC particles that incorporates complex morphological characteristics and the mixing of BC with other hygroscopic aerosols. We established a database of single‐scattering properties for these models using the invariant imbedding T‐matrix method. However, the large storage space required by this database (over 20 GB) makes it impractical for widespread applications. Therefore, we employed a deep learning method to compress the storage consumption. Two deep neural networks (DNNs) were trained using the database, enabling the prediction of all single‐scattering properties. Remarkably, the performance of the DNNs was excellent, with a coefficient of determination greater than 0.99 for all single‐scattering properties, as determined through statistical assessment. These DNN models hold great potential for various atmospheric radiation and remote sensing studies in the future. Key Points: A flexible model of partially and fully encapsulated fractal black carbon particles was developedA database of single‐scattering properties of encapsulated fractal black carbon particles was constructedTwo deep neural networks were obtained, offering a flexible approach to calculating the optical properties of black carbon aerosols [ABSTRACT FROM AUTHOR]

Active thermal radiation control of an object requires adaptive and flexible strategies to cope with emissivity engineering and its temperature dependence. On the other hand, the concept of digital coding allows a high degree of freedom in manipulating the interacting physical quantities based on local discretized features. Learning from this idea, this study put forward the manipulation of spatial infrared emission based on tungsten (W)‐doped VO2 films toward thermal coding. Here, 1‐bit coding worksheets created by low‐emissivity, that is, code '0′, and high‐emissivity, that is, code '1′, shift with materials metal‐insulator phase transition to encode emissive information in the temperature domain. It is shown experimentally that this concept has marked implications on thermal radiation control at Mid‐infrared, among which are as follows: digital anti‐counterfeiting by in‐plane spatial coding of a group of VO2 thin films with various W‐doping density and infrared camouflage by out‐of‐plane spatial coding of them. With a W‐doping gradient of 0%, 0.8%, and 1.7%, the three‐phase transition points in the temperature domain, that is, 72, 63, and 45 °C, give a remarkable modulation range of 27 °C. These phenomena pave the way for new classes of emissivity engineering for more accurate, flexible, and adaptive thermal radiation control. [ABSTRACT FROM AUTHOR]

In the current operational four‐dimensional variational (4DVar) data assimilation (DA) system of the Global Forecast System developed by the China Meteorology Administration (CMA‐GFS), all microwave observation data in cloud and precipitation regions are discarded during pre‐processing. This study implemented a Pseudo All‐Sky DA (referred to as PAS‐DA hereafter) subsystem in the operational cycle version of the CMA‐GFS (CMA‐GFS v3.2). The term "pseudo" in this study indicates that the Jacobians of brightness temperature with respect to hydrometeors from the adjoint radiative transfer model were temporarily neglected. Specifically, a liquid hydrometeor sensitive channel (23.8 GHz V pol.) of the MicroWave Radiation Imager on the platform of FengYun‐3D (FY3D‐MWRI) was selected to assess the impact of the all‐sky assimilation approach using the PAS‐DA subsystem. In the observation error model, we proposed a new cumulative distribution function (CDF) bias correction method for the cloud proxy in consideration of large discrepancies between the probability density functions (PDFs) of the observed‐cloud‐proxy and simulated‐cloud‐proxy (known as "cloud bias"). Results of single‐observation experiments justified that the present PAS‐DA subsystem could extend analysis increments to cloud regions, meanwhile correcting the errors of humidity analysis according to the mislocation of cloud distributions. In addition, the forecast experiments that were run for 1 month of the 6 hr PAS‐DA cycle in July and August 2021 demonstrate obvious superiority of the PAS‐DA over the current operational clear‐sky DA cycle: (a) root‐mean‐square errors (RMSEs) of humidity analysis were reduced by about 10% in the tropics, (b) significant improvements in humidity forecasts could be sustained for 96 hr and (c) many other forecast scores in the tropics and Southern Hemisphere also benefit from the PAS‐DA approach. Therefore, the PAS‐DA could be used for all‐sky assimilation studies and particularly for understanding how the all‐sky assimilation approach works, although the PAS‐DA serves as a transition scheme from the clear‐sky to "true" all‐sky DA. [ABSTRACT FROM AUTHOR]

The development of proton, oxygen‐ion, and electron mixed conducting materials, known as triple‐conduction materials, as cathodes for proton‐conducting solid oxide fuel cells (H‐SOFCs) is highly desired because they can increase fuel cell performance by extending the reaction active area. Although oxygen‐ion and electron conductions can be measured directly, proton conduction in these oxides is usually estimated indirectly. Because of the instability of cathode materials in a reducing environment, direct measurement of proton conduction in cathode oxide is difficult. The La0.8Sr0.2Sc0.5Fe0.5O3–δ (LSSF) cathode material is proposed for H‐SOFCs in this study, which can survive in an H2‐containing atmosphere, allowing measurement of proton conduction in LSSF by hydrogen permeation technology. Furthermore, LSSF is discovered to be a unique proton and electron mixed‐conductive material with limited oxygen diffusion capability that is specifically designed for H‐SOFCs. The LSSF is an appealing cathode choice for H‐SOFCs due to its outstanding CO2 tolerance and matched thermal expansion coefficient, producing a record‐high performance of 2032 mW cm−2 at 700°C and good long‐term stability under operational conditions. The current study reveals that a new type of proton–electron mixed conducting cathode can provide promising performance for H‐SOFCs, opening the way for developing high‐performance cathodes. [ABSTRACT FROM AUTHOR]

Dielectric Mie nanoresonators showing strong light–matter interaction at the nanoscale may enable new functionality in photonic devices, such as strong magneto‐optical effects. However, most reports so far have been focused on the enhancement of conventional magneto‐optical effects. Here, anomalous magneto‐optical effects are observed in high‐index‐contrast Si/Ce:YIG/YIG/SiO2 Mie resonators. In particular, giant modulation of light intensity in transverse magnetic configuration up to 6.4% under s‐polarized incidence appears, which is non‐existent in planar magneto‐optical thin films. A large rotation of transmitted light polarization in longitudinal magnetic configuration is also observed, which is two orders of magnitude higher than for planar magneto‐optical thin films. These phenomena are originated from the unique circular displacement current when exciting magnetic resonances in the Mie resonators, which change the electric field direction locally. This work indicates an uncharted territory of light polarization control based on complex modal profiles in all‐dielectric magneto‐optical Mie resonators and metasurfaces. [ABSTRACT FROM AUTHOR]

The development of electromagnetic interference (EMI) shielding materials with excellent EMI shielding effectiveness (SE), and superior mechanical performance is of great importance in daily life and in the military, where they are used for intelligent transportation systems and ammunition. Generally, shielding performances can be realized via reflection loss and absorption loss. However, it is still a challenge to enhance these two kinds of electromagnetic wave loss in the same material at the same time to achieve ideal shielding performance. Herein, a flexible Ag NDs/CNT@PC/Ni‐9 film composed of five conductive layers and four porous layers is prepared by alternating Ag NDs/CNT layers and PC/Ni layers through self‐assembly. The obtained film with a thickness of 890 μm exhibits a remarkable SE performance of 138 dB in the X‐band. Additionally, with a series of continuous volcanic mechanical impacts (>10 000 g), the maximum instantaneous acceleration is decreased by 30.02% due to the buffering of the film, which constitutes a much‐improved energy absorption cushion relative to that of traditional buffering materials, such as foam metal and rubber. A material integrated with strong EMI shielding and high mechanical shock resistance is designed, which provides an effective strategy for the development of functional materials for extreme environments. [ABSTRACT FROM AUTHOR]

Nonreciprocal photonic devices are essential components of classical optical information processing. It is interesting and important to investigate their feasibility in the quantum world. In this work, a single‐photon non‐reciprocal dynamical transmission experiment has been performed with an on‐chip silicon nitride (SiN)‐based magneto‐optical (MO) isolator. The measured isolation ratio for single photons achieved is 12.33 dB, consistent with the result of the classical test, which proves the functionality of our on‐chip isolator. The quantum coherence of the passing single photons is further verified using high‐visibility quantum interference. This work will promote on‐chip nonreciprocal photonic devices within the integrated quantum circuits and help introduce novel phenomena in quantum information processes. [ABSTRACT FROM AUTHOR]

The backscattering optical properties of an ensemble of randomly oriented dust particles at a wavelength of 355 nm were comprehensively studied by examining the invariant imbedding T‐matrix results of the super‐spheroid dust model. In particular, we focused on the lidar ratio (S $S$) and depolarization ratio (δ $\delta $) relations of dust aerosols to aid interpretation of data from the Atmospheric Lidar (ATLID) instrument that will be onboard the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) satellite. Super‐spheroid models with various aspect ratios (α $\alpha $), roundness parameters (n) $(n)$, and refractive indices were investigated over a wide range of particle sizes and compared to the observation data of the National Aeronautics and Space Administration (NASA) Langley 355‐nm airborne high spectral resolution lidar. We found that super‐spheroid dust particles with different sets of n $n$ and α $\alpha $ could be used to model almost the entire range of the observed joint distributions of S $S$ and δ $\delta $. The S−δ $S-\delta $ relation could effectively discriminate among dust particle types. The observed S $S$ and δ $\delta $ values with the largest population density were best covered by models with n > 2, especially by those with n $n$ varying from 2.4 to 3.0. Plain Language Summary: Dust aerosols are irregularly shaped. Dust shape has a significant impact on the modeling of lidar observations. In this work, super‐spheroid models (the conventional spheroid model is a special case) were used to study the impacts of nonsphericity and irregularity on lidar observations. In particular, we were interested in the lidar and depolarization ratios, because these ratios have proven useful for distinguishing among aerosol types in the atmosphere and will be measurable by the future Earth Cloud, Aerosol, and Radiation Explorer (EarthCARE) satellite. Because the lidar and depolarization ratios can be affected by multiple factors, including dust shape, refractive indices, and particle sizes, systematic theoretical studies related to these factors were conducted. Furthermore, we compared the theoretical simulations with NASA Langley airborne high spectral resolution lidar data, and found that super‐spheroid models could be used to explain the wide variation of dust optical properties found in the lidar data. The present study confirmed that dust particles represented by super‐spheroid models can be useful in lidar remote sensing applications. Based on this, the optimal parameters of super‐spheroid models can be used to parameterize dust shapes. Key Points: The backscattering optical properties of dust aerosols were modeled systematically using homogeneous super‐spheroidsA comprehensive survey of the lidar ratio‐depolarization ratio relations produced by super‐spheroids at 355 nm wavelength was conductedSuper‐spheroids could be used to explain the wide variation of dust optical properties found in the high spectral resolution lidar data [ABSTRACT FROM AUTHOR]

The evolution of landfalling Typhoon Fitow in the western North Pacific in 2013 is simulated with an emphasis on the direct radiative effect of sea‐salt aerosols (SSAs) on the precipitation of Fitow. The inhomogeneous SSAs, formed under the environment with low relative humidity (50%–70%), exhibit different optical properties (particular the decreased asymmetry factor) compared with the commonly used homogeneous sea‐salt droplets. We find that incorporating the inhomogeneity of SSAs in the Weather Research and Forecasting (WRF) model decreases the simulated rainfall of Fitow in coastal regions where the continental dry air intrudes. Fundamentally, the cooling effect induced by the particle inhomogeneity and its hysteresis increase atmospheric stability and weaken vertical velocity, which reduce the accumulated rainfall of Fitow. These findings of radiation‐related effects of SSAs provide a new clue for improving the physical processes responsible for precipitation of tropical cyclones in numerical models. Plain Language Summary: For the landfalling tropical cyclones (TCs) over the western North Pacific, the intrusion of dry air into the TCs is extensive and significant since the dry air may come from both a high‐pressure system and the dry mid‐to‐high‐latitude continent. Under the dry environment, the sea‐salt aerosols (SSAs) appear to be coated inhomogeneous spheres according to previous findings. However, the physical process associated with the inhomogeneity of the SSAs has never been considered in both research and operational forecast of TCs, which may partly account for the discrepancy between simulation (or forecast) and observation of TCs. This study explores the direct radiative effects of inhomogeneous SSAs on the precipitation of a landfalling TC in 2013 first, and reveals that the cooling effect associated with the inhomogeneity of SSAs increases the stability of the low‐level troposphere and weakens the vertical velocity, which finally suppresses the total rainfall of the TC in the coastal regions, suggesting that the inhomogeneity of SSAs should be carefully considered in numerical models for improving the precipitation forecast of landfalling TCs. Key Points: Direct radiative effects of inhomogeneous sea‐salt aerosols (SSAs) on the precipitation of a landfalling tropical cyclone (TC) are exploredIncorporating the inhomogeneity of SSAs enhances atmospheric stability, weakens vertical velocity and reduces the rainfall of the TCThe results provide a new clue to improve the physical processes responsible for precipitation associated with TCs in numerical models [ABSTRACT FROM AUTHOR]

Black carbon (BC) strongly absorbs solar radiation, contributing to global warming. Absorption enhancement of BC particles is difficult to quantify due to an inadequate representation of their complex morphology and mixing structures, as well as interaction with radiation. Here, we apply a 3D method accounting for detailed BC mixing structures to predict the absorption enhancement of individual BC particles (Eabs) and the total BC particle population (Eabs, bulk). The diverse range of mixing structures in individual BC particles leads to variable Eabs that could hardly be predicted by empirical approximations. We find that the volume proportion of the BC embedded in coating (F) determines Eabs when the particle to BC core diameter ratio (Dp/Dc) is larger than 2.0. Our findings reveal the potential mechanism behind the differences in observed and modeled Eabs, bulk. The framework builds a bridge connecting the microscopic mixing structure of individual BC particle with Eabs, bulk. Plain Language Summary: Absorption by black carbon (BC) in the atmosphere strongly affects radiative balance and global climate. The large discrepancies in observed and modeled BC absorption enhancements raise a hot debate. Through applying a new 3D shape model based on electron microscope observations, we propose a new framework that estimates BC absorption enhancement through accounting for mixing structure diversity in individual particles. Our results reveal that the diverse range of mixing structures in individual particles in ambient air leads to complex absorption enhancement that could hardly be predicted by the empirical approximation. The bulk absorption enhancements based on diverse mixing structures provide an explanation for the globally disparate results from laboratory and field observations. The new framework linking microphysical structures to bulk BC optical properties can be used to improve assessment of climate impact. Key Points: The impact on absorption enhancement by embedded fraction is significantly enhanced when BC particle to core diameter ratio >2.0The embedded fraction and coating thickness in aged BC particles can lead to significant differences in bulk absorption enhancementA new bridge is built to connect the microscopic mixing structure of individual aged BC particles with bulk absorption enhancement of BC [ABSTRACT FROM AUTHOR]

Black carbon (BC) aerosols strongly absorb the solar radiation, affecting the regional and global climate through direct and indirect radiative forcing. The optical properties of BC are critical factors to estimate their radiative forcing. However, the optical absorption of BC is still under controversy partially due to the weakness in quantifying their complex morphology and mixing structures. Although a Discrete Dipole Approximation (DDA) can calculate optical properties of fine particles with arbitrary shapes, an appropriate definition of realistic BC shape models for optical simulation is essentially required. Here we present a novel Electron‐Microscope‐to‐BC‐Simulation (EMBS) tool to construct realistic BC shape models with various morphology and mixing structures for optical calculation using DDA. The optical properties of BC particles with different particle morphology, coating thickness, and embedded fraction (F) are estimated based on electron microscope. We find that absorption enhancement (Eabs) of the realistic irregular model is larger than that of the present commonly used spherical model (i.e., BC aggregate with spherical coating). The BC core morphology greatly influences Eabs of the embedded BC particles with irregular coating when the volume‐equivalent‐diameter ratio of particle to core (Dp/Dc) is larger than 1.8. The F significantly influences Eabs of BC particles, suggesting that the mixing structure between coating and core is an important factor to determine the optical absorption of aged BC particles. The study highlights that the BC core morphology, coating shape, coating thickness, and mixing structures influence their optical properties and should be considered as important variables in climate models. Plain Language Summary: Black carbon (BC) is one of the most important aerosol impacting the regional and global climate change due to its strong optical absorption in the atmosphere. However, it is challenging to precisely estimate the BC optical properties using instruments and numerical models because of its complex morphology and mixing structures in individual particles. This study for the first time presents a novel tool (named as EMBS) to construct realistic 3D shape models based on real BC particles from electron microscopic images for their optical calculation. We found that the commonly used spherical shape models may underestimate the absorption enhancement (Eabs) of BC particles. The mixing structures between BC and non‐BC materials in individual particles can significantly influence their Eabs. The novel EMBS builds a bridge between microscopic observation and BC optical calculation, which has strong implications for reducing the bias of optical calculation and providing important variables in estimating BC climate effects in the future. Key Points: A novel tool is used to construct black carbon (BC) shape models with various morphology and mixing structures based on electron microscopeThe commonly used spherical models may underestimate the absorption enhancement of BC particlesThe embedded fraction and coating shape significantly influence absorption enhancement through determining their mixing structures [ABSTRACT FROM AUTHOR]

In this study, we attempted to address the frozen hydrometeor habit vertical inhomogeneity (FHHVI) effects on microwave radiative transfer simulations. For simplification, we focused on a "two habits and two layers" FHHVI scheme in which two different ice habits can be assumed to be above and below a fixed habit boundary line of 325 hPa as suggested by studies of tropical cyclone vertical structure. The aforementioned FHHVI scheme was implemented into a radiative transfer for the Television Infrared Observation Satellite (TIROS) operational vertical sounder (RTTOV), which allows for close examination of the FHHVI effect on the radiative transfer process. Four scenarios (thin plate, dendrite, thin plate over dendrite, and dendrite over thin plate) were considered in the simulations at frequencies ranging from 10 to 183 GHz. We found that FHHVI has an obvious impact on the brightness temperature (BT) simulations. For real case studies, we considered the 2018 tropical cyclone Jebi in the Western Pacific basin. The hydrometeor profiles forecasted by the Global/Regional Assimilation and Prediction System (GRAPES) regional numerical weather prediction (NWP) model were used, and the simulated results were compared with observations from the instruments aboard on the Fengyun‐3D satellite, which recorded 61 overpasses during the life span of typhoon Jebi. We found that the overall performance of the BT simulations over multichannels could be improved by considering FHHVI effects. Specifically, the total penalty values that quantify the spectral consistency were 63.05 (dendrite), 43.88 (thin plate), 46.23 (dendrite over thin plate), and 39.03 (thin plate over dendrite), respectively. Key Points: The frozen hydrometeor habit vertical inhomogeneity (FHHVI) has significant impacts on microwave radiative transfer simulationsIncorporating the FHHVI into the radiative transfer could improve the spectrum consistency when compared with Fengyun‐3D observationsFHHVI is believed promising in the way forward for improving radiative transfer simulations with relevant applications in data assimilation [ABSTRACT FROM AUTHOR]

Dust shortwave absorbability suffers from significant uncertainties. We investigated the radiative effects of dust aerosols from the circum‐Tibet region using four shortwave absorbability schemes and examined their impacts on the East Asian summer monsoon by using the Community Earth System Model (CESM). We adopted superspheroidal models to compute dust aerosol optical properties and found that more absorptive particles have larger asymmetry factor and lower single‐scattering albedo. Meiyu precipitation, as a part of the East Asian summer monsoon, is weakened by dust aerosols, particularly for the convective precipitation. The mechanism is that dust aerosols transported mainly from the Gobi desert radiatively heat the lower atmosphere to the north of the Meiyu rainband and decrease the meridional temperature gradient, leading to the weakening of the midtropospheric westerly jet over the Meiyu rainband, which is important for convection. More absorptive dust aerosols with a stronger radiative heating effect inhibit more convective Meiyu precipitation. Plain Language Summary: The circum‐Tibet region including the Taklimakan and Gobi deserts is the major source region of dust aerosols in East Asia particularly during the spring and summer seasons. Meiyu, as a part of the East Asian summer monsoon, generally occurs from mid‐June to mid‐July and often shows a tilt rain band extending from southwest to east China. The Letter reports on our finding about the relationship between dust shortwave absorbability (the amount of solar radiation absorbed by dust) and Meiyu precipitation. For weakly absorptive dust aerosols, convective Meiyu precipitation is rarely changed by dust aerosols; however, for strongly absorptive dust aerosols, convective Meiyu precipitation is significantly decreased. The impact of dust absorbability on Meiyu precipitation is explained through atmospheric heating rate, temperature, and wind field changes. This Letter emphasizes the urgent need of a more accurate knowledge of dust shortwave absorbability for climate modeling since significant uncertainties of refractive indices exist and new evidences show that Asian dust could be less absorptive than previously believed. Key Points: Dust shortwave absorbability affects single‐scattering albedo and asymmetry factorDust aerosols inhibit convective Meiyu precipitation depending on absorbabilityMidtropospheric westerly jet is weakened by dust aerosols causing decreased convective precipitation [ABSTRACT FROM AUTHOR]

Sea salt aerosols were assumed to be homogeneous spheres in most climate models. However, observations show that sea salt particles are inhomogeneous during the deliquesce and crystallization processes. Using a two‐layer sphere model, we found that backscattering of solar radiation associated with sea salts is underestimated in homogeneous sea salt models. The Community Earth System Model is used to assess the inhomogeneity effect on direct radiative forcing. For global climate model simulation, the inhomogeneity effect on radiative transfer is found to be small as high RHs over widespread oceans suppress the impact of inhomogeneity. On the other hand, in coastal regions, the inhomogeneity effect can cause up to 10% radiative forcing difference of sea salt aerosols. The inhomogeneity effect of sea salt aerosols has to be considered over coastal regions, especially in the Mediterranean, Australia, and the eastern coast of South America. Plain Language Summary: In a humid environment, solid sea salt particles can be coated with water. Sea salt aerosol has a cooling effect on the Earth, but coated sea salt has even stronger cooling effect. However, in most climate models, coated sea salt is not considered. This study confirms that coated sea salt aerosols may not significantly affect the global radiation budget, but they should definitely be considered in the coastal climate where large changes in relative humidity are evident. Key Points: For some range of relative humidity (50‐80%), sea salt is assumed to be an inhomogeneous two‐layer sphereThe inhomogeneity of sea salt decreases the asymmetry factor and increases backscattering of solar radiationInhomogeneity has a relatively large impact (up to 10%) on sea salt radiative forcing over coastal waters [ABSTRACT FROM AUTHOR]

Abstract: Coral‐like, clean PtPd bimetallic nanochains with controlled composition are successfully synthesized by using carbon monoxide as reducing agent and soft‐template. The Pt74Pd26 nanochain catalyst exhibits a much more positive half‐wave potential than pure Pt nanochains (∼35 mV) and commercial Pt/C (∼30 mV) toward the oxygen reduction reaction. Meanwhile, oxygen reduction on the Pt74Pd26 electrode has only a 4 mV degradation in half‐wave potential over 5,000 cycling period, showing superior electrochemical stability. The enhanced performance could be due to the modified electronic structure (such as downshifted d‐band center and weakened bonding to oxygenated species) and the coral‐like nanochains with mesoporous structure and clean surface. This work may demonstrate a universal approach to facilitate screening of high‐efficiency catalysts for broad energy conversion/storage systems and sensing devices. [ABSTRACT FROM AUTHOR]

Abstract: The nonsphericity and inhomogeneity of marine aerosols (sea salts) have not been addressed in pertinent radiative transfer calculations and remote sensing studies. This study investigates the optical properties of nonspherical and inhomogeneous sea salts using invariant imbedding T‐matrix simulations. Dry sea salt aerosols are modeled based on superellipsoidal geometries with a prescribed aspect ratio and roundness parameter. Wet sea salt particles are modeled as coated superellipsoids, as spherical particles with a superellipsoidal core, and as homogeneous spheres depending on the level of relative humidity. Aspect ratio and roundness parameters are found to be critical to interpreting the linear depolarization ratios (LDRs) of NaCl crystals from laboratory measurements. The optimal morphology parameters of NaCl necessary to reproduce the measurements are found to be consistent with data gleaned from an electron micrograph. The LDRs of wet sea salts are computed based on inhomogeneous models and compared with the measured data from ground‐based LiDAR. The dependence of the LDR on relative humidity is explicitly considered. The increase in the LDR with relative humidity at the initial phase of deliquescence is attributed to both the size increase and the inhomogeneity effect. For large humidity values, the LDR substantially decreases because the overall particle shape becomes more spherical and the inhomogeneity effect in a particle on the LDR is suppressed for submicron sea salts. However, the effect of inhomogeneity on optical properties is pronounced for coarse‐mode sea salts. These findings have important implications for atmospheric radiative transfer and remote sensing involving sea salt aerosols. [ABSTRACT FROM AUTHOR]

Purpose: To differentiate pancreatobiliary-type from intestinal-type periampullary carcinomas using combined magnetic resonance cholangiopancreatography (MRCP), contrast-enhanced MRI, and diffusion-weighted imaging (DWI). Materials and Methods: MRI (3.0T) results of 41 patients with pathologically confirmed periampullary carcinoma were retrospectively assessed. Two radiologists, blinded to histologic type of each tumor, evaluated image findings independently. MRCP image features, enhancement pattern, and apparent diffusion coefficient (ADC) values were analyzed. Independent-sample t-test, chi-square, or Fisher's exact test were used to determine differential image findings between the pancreatobiliary-type and the intestinal-type group. Cohen's κ statistic or interclass correlation coefficient (ICC) were used to evaluate interobserver agreement between two observers. Univariate and multiple logistic regression analysis were performed to identify MRI features with predictive values. Results: On the basis of hematoxylin-eosin staining, 27 patients were classified as having pancreatobiliary-type carcinomas, and 14 patients the intestinal type. The pancreatobiliary-type carcinomas more commonly showed progressive enhancement than the intestinal type (P = 0.003). The minimum ADC (ADCmin ) value of the pancreatobiliary-type group ([0.95 ± 0.21] × 10(-3) mm(2) /s) was significantly lower than the intestinal-type group ([1.10 ± 0.25] × 10(-3) mm(2) /s) (P = 0.047). For interobserver agreement, the κ values and ICCs for all parameters exceeded 0.8, indicating almost perfect agreement. At multiple logistic regression analysis, the enhancement pattern was the only significant independent predictor (P = 0.011, odds ratio [OR] = 0.105). When the enhancement pattern and ADCmin were used in combination, we could identify 70.4% of pancreatobiliary-type and 78.6% of intestinal-type carcinomas. Conclusion: Progressive enhancement and low ADCmin values suggest a pancreatobiliary-type periampullary carcinoma. [ABSTRACT FROM AUTHOR]

Off-axis deposition of Ti and CoCrPt films onto lithographically patterned templates has been used to make nanostructures with a lateral thickness variation that allows the tuning of the magnetic anisotropy. CoCrPt rectangles of 1 μm × 725 nm without a thickness variation show an out-of-plane easy axis and a single-domain configuration after demagnetization. On the other hand, rectangles with a thickness variation along their longer dimension show an out-of-plane multidomain state, but an in-plane vortex configuration occurs when the thickness variation is along the shorter dimension. The evolution of the magnetic behavior is understood from the change in both Ti and CoCrPt thicknesses and their effects on the magnetic anisotropy, and provides a simple method for controlling the magnetic state and reversal process of patterned nanostructures. [ABSTRACT FROM AUTHOR]

Yttrium and indium co-doped barium zirconate is investigated to develop a chemically stable and sintering active proton conductor for solid oxide fuel cells (SOFCs). BaZr0.8Y0.2-xInxO3- δ possesses a pure cubic perovskite structure. The sintering activity of BaZr0.8Y0.2-xInxO3- δ increases significantly with In concentration. BaZr0.8Y0.15In0.05O3- δ (BZYI5) exhibits the highest total electrical conductivity among the sintered oxides. BZYI5 also retains high chemical stability against CO2, vapor, and reduction of H2. The good sintering activity, high conductivity, and chemical stability of BZYI5 facilitate the fabrication of durable SOFCs based on a highly conductive BZYI5 electrolyte film by cost-effective ceramic processes. Fully dense BZYI5 electrolyte film is successfully prepared on the anode substrate by a facile drop-coating technique followed by co-firing at 1400 °C for 5 h in air. The BZYI5 film exhibits one of the highest conductivity among the BaZrO3-based electrolyte films with various sintering aids. BZYI5-based single cells output very encouraging and by far the highest peak power density for BaZrO3-based proton-conducting SOFCs, reaching as high as 379 mW cm−2 at 700 °C. The results demonstrate that Y and In co-doping is an effective strategy for exploring sintering active and chemically stable BaZrO3-based proton conductors for high performance proton-conducting SOFCs. [ABSTRACT FROM AUTHOR]

Atmospheric dust particles are known to have diverse and irregular morphologies. In order to account for nonsphericity, the spheroidal model with an aspect ratio distribution has been extensively used for modeling the optical properties of dust. The spheroidal model is superior to the spherical shape assumption, but it requires further improvement. In this study, superspheroids' modeling capabilities were systematically examined by comprehensively comparing the spheroid's and superspheroid's scattering matrices. Superspheroids have one more degree of freedom than spheroids and can be nonspherical at an aspect ratio of unity. The invariant imbedding T‐matrix and the improved geometrical optics methods were employed to compute superspheroids' single‐scattering properties with a wide distribution of aspect ratios and a number of roundness parameters. We then assessed the spheroidal and superspheroidal models' applicability for simulating the scattering matrices of 25 dust samples from the Amsterdam‐Granada Light Scattering Database. It was found that extreme aspect ratios for spheroids in reproducing the measurements were unnecessary if superspheroids were used. Even with equi‐probable aspect ratio distribution, superspheroids with constrained roundness parameters (from 2.4 to 3.0) could achieve better performances in concurrently matching six nonzero scattering matrix elements from the laboratory measurements. Moreover, superspheroids demonstrated better performances than spheroids in achieving spectral consistency for modeling dust scattering matrices. Therefore, superspheroids appear to be highly promising for atmospheric radiative transfer and remote sensing applications. Key Points: Superspheroids were used to model dust aerosols' scattering matrices, and comprehensive comparisons between scattering matrix simulations and measurements were conducted for 25 samples from the Amsterdam‐Granada Light Scattering DatabaseSuperspheroids were shown to be superior to spheroids in reproducing the measurements and show much better performances in concurrently matching the phase function and polarization characteristics at 441.6 and 632.8 nmSuperspheroids with constrained roundness parameter appear to be highly promising for dust radiative transfer simulations [ABSTRACT FROM AUTHOR]

Review: 113 refs. [ABSTRACT FROM AUTHOR]

Review: 138 refs. [ABSTRACT FROM AUTHOR]